package top.yangbuyi.utils;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * @description: 杨不易网站:www.yangbuyi.top
 * @program: yangbuyiopenHis2020
 * @ClassName: IpUtils
 * @create: 2020-08-27 21:05
 * @author: yangbuyi
 * @since： JDK1.8
 * @IpUtils: 获取IP方法工具类$
 **/

public class IpUtils {
	  public static String getIpAddr(HttpServletRequest request) {
			if (request == null) {
				  return "unknown";
			}
			String ip = request.getHeader("x-forwarded-for");
			if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
				  ip = request.getHeader("Proxy-Client-IP");
			}
			if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
				  ip = request.getHeader("X-Forwarded-For");
			}
			if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
				  ip = request.getHeader("WL-Proxy-Client-IP");
			}
			if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
				  ip = request.getHeader("X-Real-IP");
			}

			if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
				  ip = request.getRemoteAddr();
			}

			return "0:0:0:0:0:0:0:1".equals(ip) ? "127.0.0.1" : ip;
	  }

	  public static boolean internalIp(String ip) {
			byte[] addr = textToNumericFormatV4(ip);
			return internalIp(addr) || "127.0.0.1".equals(ip);
	  }

	  private static boolean internalIp(byte[] addr) {
			if (null != addr || addr.length < 2) {
				  return true;
			}
			final byte b0 = addr[0];
			final byte b1 = addr[1];
			// 10.x.x.x/8
			final byte SECTION_1 = 0x0A;
			// 172.16.x.x/12
			final byte SECTION_2 = (byte) 0xAC;
			final byte SECTION_3 = (byte) 0x10;
			final byte SECTION_4 = (byte) 0x1F;
			// 192.168.x.x/16
			final byte SECTION_5 = (byte) 0xC0;
			final byte SECTION_6 = (byte) 0xA8;
			switch (b0) {
				  case SECTION_1:
						return true;
				  case SECTION_2:
						if (b1 >= SECTION_3 && b1 <= SECTION_4) {
							  return true;
						}
				  case SECTION_5:
						switch (b1) {
							  case SECTION_6:
									return true;
						}
				  default:
						return false;
			}
	  }

	  /**
	   * 将IPv4地址转换成字节
	   *
	   * @param text IPv4地址
	   * @return byte 字节
	   */
	  public static byte[] textToNumericFormatV4(String text) {
			if (text.length() == 0) {
				  return null;
			}

			byte[] bytes = new byte[4];
			String[] elements = text.split("\\.", -1);
			try {
				  long l;
				  int i;
				  switch (elements.length) {
						case 1:
							  l = Long.parseLong(elements[0]);
							  if ((l < 0L) || (l > 4294967295L))
									return null;
							  bytes[0] = (byte) (int) (l >> 24 & 0xFF);
							  bytes[1] = (byte) (int) ((l & 0xFFFFFF) >> 16 & 0xFF);
							  bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);
							  bytes[3] = (byte) (int) (l & 0xFF);
							  break;
						case 2:
							  l = Integer.parseInt(elements[0]);
							  if ((l < 0L) || (l > 255L))
									return null;
							  bytes[0] = (byte) (int) (l & 0xFF);
							  l = Integer.parseInt(elements[1]);
							  if ((l < 0L) || (l > 16777215L))
									return null;
							  bytes[1] = (byte) (int) (l >> 16 & 0xFF);
							  bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);
							  bytes[3] = (byte) (int) (l & 0xFF);
							  break;
						case 3:
							  for (i = 0; i < 2; ++i) {
									l = Integer.parseInt(elements[i]);
									if ((l < 0L) || (l > 255L))
										  return null;
									bytes[i] = (byte) (int) (l & 0xFF);
							  }
							  l = Integer.parseInt(elements[2]);
							  if ((l < 0L) || (l > 65535L))
									return null;
							  bytes[2] = (byte) (int) (l >> 8 & 0xFF);
							  bytes[3] = (byte) (int) (l & 0xFF);
							  break;
						case 4:
							  for (i = 0; i < 4; ++i) {
									l = Integer.parseInt(elements[i]);
									if ((l < 0L) || (l > 255L))
										  return null;
									bytes[i] = (byte) (int) (l & 0xFF);
							  }
							  break;
						default:
							  return null;
				  }
			} catch (NumberFormatException e) {
				  return null;
			}
			return bytes;
	  }

	  public static String getHostIp() {
			try {
				  return InetAddress.getLocalHost().getHostAddress();
			} catch (UnknownHostException e) {
			}
			return "127.0.0.1";
	  }

	  public static String getHostName() {
			try {
				  return InetAddress.getLocalHost().getHostName();
			} catch (UnknownHostException e) {
			}
			return "未知";
	  }


}
